Pump housings of the spiral housing construction type discussed here are applied in technology in a diverse manner. Such pump housings are used for heating circulation pumps for example which nowadays are often equipped with electronic speed controllers which open up an extended field of application. Even if the operating conditions of the pump are detected via the electrical data of the motor, however a differential pressure measurement is normally necessary for inclusion into a closed-loop control and this measurement detects at least the pressure difference between the suction side and the pressure side of the pump. In order to avoid external pipework and long conduit connections, it is counted as belonging to the state of the art, to attach such a differential pressure sensor on the pump housing itself.
From EP 0 774 583 A1, it is known to provide an assembly basis next to the pressure connection and connection flange, on a rib of the pump housing, and this assembly basis comprises a bore projecting into the rib, as a receiver for the differential pressure sensor. This bore is connected via channels to the suction port of the pump on the one hand, and to the pressure channel in the region of the connection flange on the other hand.
One disadvantage of this known arrangement is the fact that the channels in the pump housing consisting typically of a casting must be included in this casting, which requires some effort with regard to tooling technology and in particular necessitates the application of lost cores which means significant costs, in particular with large-scale manufacture.